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31.
Salman Al-Kofahi Caiti Steele Dawn VanLeeuwen Rolston St. Hilaire 《Urban Forestry & Urban Greening》2012,11(3):291-301
Accurate information on existing residential landscapes is essential for framing ordinances and monitoring residential water use in the Urban Greenspace Ecosystem. We classified residential landscapes of New Mexico's largest city, Albuquerque, to explore the spatial distribution of residential greenspace and its composition among zip codes and median incomes. Geographic Information System (GIS) vector files including parcels, city limits, zip codes and land-use maps, were integrated with ownership information. The database was stratified by Albuquerque's 16 zip codes. Four hundred eighty residential landscapes were selected randomly for study. Very high spatial resolution (0.15 m) 2008 true color aerial photographs and the object-oriented supervised classification module in ENVI EX were used to identify residential features. Spatial and textural variables, created by image segmentation, were classified using the K-Nearest Neighbor (K-NN) algorithm embedded in ENVI EX. Classification accuracy was 89%. Larger greenspace, tree, shrub, and grass areas were in larger parcels. Landscapes in lower income groups and older zip codes include larger greenspace and tree cover because of mature tree sizes, while grass dominated landscapes of higher income groups and newer zip codes. This knowledge of residential vegetation distribution could serve as a basis for policy makers, planners, and water conservation officers wishing to enact ordinances and regulations that govern the urban residential landscape. 相似文献
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OBJECTIVE: To determine pharmacokinetics of buprenorphine in dogs after i.v. administration. ANIMALS: 6 healthy adult dogs. PROCEDURES: 6 dogs received buprenorphine at 0.015 mg/kg, i.v. Blood samples were collected at time 0 prior to drug administration and at 2, 5, 10, 15, 20, 30, 40, 60, 90, 120, 180, 240, 360, 540, 720, 1,080, and 1,440 minutes after drug administration. Serum buprenorphine concentrations were determined by use of double-antibody radioimmunoassay. Data were subjected to noncompartmental analysis with area under the time-concentration curve to infinity (AUC) and area under the first moment curve calculated to infinity by use of a log-linear trapezoidal model. Other kinetic variables included terminal rate constant (k(el)) and elimination half-life (t(1/2)), plasma clearance (Cl), volume of distribution at steady state (Vd(ss)), and mean residence time (MRT). Time to maximal concentration (T(max)) and maximal serum concentration (C(max)) were measured. RESULTS: Median (range) values for T(max) and MRT were 2 minutes (2 to 5 minutes) and 264 minutes (199 to 600 minutes), respectively. Harmonic mean and pseudo SD for t(1/2) were 270+/-130 minutes; mean +/- SD values for remaining pharmacokinetic variables were as follows: C(max), 14+/-2.6 ng/mL; AUC, 3,082+/-1,047 ng x min/mL; Vd(ss), 1.59+/-0.285 L/kg; Cl, 5.4+/-1.9 mL/min/kg; and, k(el), 0.0026+/-0.0,012. CONCLUSIONS AND CLINICAL RELEVANCE: Pharmacokinetic variables of buprenorphine reported here differed from those previously reported for dogs. Wide variations in individual t(1/2) values suggested that dosing intervals be based on assessment of pain status rather than prescribed dosing intervals. 相似文献
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Bailey KS Dewey CW Boothe DM Barone G Kortz GD 《Journal of the American Veterinary Medical Association》2008,232(6):867-872
OBJECTIVE: To assess pharmacokinetics, efficacy, and tolerability of oral levetiracetam administered as an adjunct to phenobarbital treatment in cats with poorly controlled suspected idiopathic epilepsy. DESIGN-Open-label, noncomparative clinical trial. ANIMALS: 12 cats suspected to have idiopathic epilepsy that was poorly controlled with phenobarbital or that had unacceptable adverse effects when treated with phenobarbital. PROCEDURES: Cats were treated with levetiracetam (20 mg/kg [9.1 mg/lb], PO, q 8 h). After a minimum of 1 week of treatment, serum levetiracetam concentrations were measured before and 2, 4, and 6 hours after drug administration, and maximum and minimum serum concentrations and elimination half-life were calculated. Seizure frequencies before and after initiation of levetiracetam treatment were compared, and adverse effects were recorded. RESULTS: Median maximum serum levetiracetam concentration was 25.5 microg/mL, median minimum serum levetiracetam concentration was 8.3 microg/mL, and median elimination half-life was 2.9 hours. Median seizure frequency prior to treatment with levetiracetam (2.1 seizures/mo) was significantly higher than median seizure frequency after initiation of levetiracetam treatment (0.42 seizures/mo), and 7 of 10 cats were classified as having responded to levetiracetam treatment (ie, reduction in seizure frequency of >or=50%). Two cats had transient lethargy and inappetence. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that levetiracetam is well tolerated in cats and may be useful as an adjunct to phenobarbital treatment in cats with idiopathic epilepsy. 相似文献
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Matthew Capitanio Dawn M Zimmerman Michael Douglass Terry Dew 《Journal of zoo and wildlife medicine》2008,39(2):270-273
A 16-yr-old, castrated male lion-tailed macaque (Macaca silenus) presented with acute bilateral pelvic limb paralysis. Cisternal and lumbar myelograms demonstrated right-sided spinal cord compression at T13-L1. During an extradural hemilaminectomy, chronically ruptured disk material was removed at T13-L1, with moderate venous dilatation observed cranially. The macaque fully recovered from clinical signs within 2 mo. 相似文献
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Levy Carvalho Gomes Richard Philip Brinn Jaydione Luiz Marcon Lucelle Araújo Dantas Franmir Rodrigues Brandão Janessa Sampaio de Abreu Paulo Evandro Mendes Lemos Dawn Michelle McComb & Bernardo Baldisserotto 《Aquaculture Research》2009,40(2):157-165
The objective of this experiment was to test the probiotic Efinol® L during transportation of cardinal tetra, Paracheirodon axelrodi (Schultz). For the transportation, fish were distributed in 18 plastic tanks, of which nine contained the Efinol® L (10 mg L−1 ; probiotic treatment) and the remaining had no probiotic (control treatment). Transport lasted 24 h and three different boxes of each treatment were sampled at 3, 12 and 24 h. Up to the 12-h sampling period, no significant difference in the survival was observed; on the other hand, survival was higher at the end of the transport (24 h) in the probiotic treatment. No significant difference was found in dissolved oxygen and temperature between treatments. Conductivity, pH and alkalinity increased along the transport, but without a difference between treatments. Ammonia increased in all treatments, although it was significantly lower in the probiotic group at 24 h. Cortisol levels were significantly higher in all transported fish when compared with the basal values. At 24 h, cortisol levels in control fish were significantly higher than those in the probiotic treatment. With the observed results, we are able to conclude that the probiotic Efinol® L is efficient during cardinal transport, lowering the mortality and helping maintain water quality possibly by lowering metabolic wastes. 相似文献